I mean, you can do that with any image. Adding the exclamation point before the link tells Lemmy to embed the image instead. And anything you put in the brackets turns into alt text, which users can view by hovering over the image.

My point was mostly to be able to add it to my discord server (or anywhere that allows custom emoji’s, really.) Since they use a standardized 128x128 image size, it’s just a matter of scaling it down to that and trimming it so it’s transparent.